Question Video: Finding the Perimeter of a Rectangle given Its Dimensions Mathematics • 3rd Grade

Video Transcript

Find the perimeter of a rectangle whose length is 35 centimeters and width is 15 centimeters.

Let’s solve this problem by first sketching a picture of this rectangle. Okay, here we have a rectangle. We’ll need to label it with the length and width. The length of this rectangle is 35 centimeters. The width of this rectangle is 15 centimeters. To find the perimeter, we’ll need to find the sum of all sides of this rectangle. To find the perimeter of this rectangle, we’ll need to know the measure of all four sides. Across from the length of 35 centimeters, will be another length of 35 centimeters. Across from the width of 15 centimeters, is another width of 15 centimeters. In a rectangle, opposite sides have the same measures.

Okay, back to finding the perimeter. The perimeter will equal every side added together. 35 centimeters plus 15 centimeters plus 35 centimeters plus 15 centimeters. 35 plus 15 equals 50 centimeters. 35 plus 15 equals another 50 centimeters. We add 50 plus 50 which equals 100 centimeters.

The distance around this rectangle or the sum of all sides, the perimeter, is 100 centimeters.